.preview-pdf-box{
    .btn-group{
        position: absolute;
        top: 50%;
        left: 0;
        width: 90%;
        z-index: 9999;
        transform: translateY(-50%);
        .btn{
            color: #fff;
            cursor: pointer;
            content: '';
            width: 44px;
            height: 44px;
            background-color: rgba(97, 97, 97, 0.8);
            border-radius: 50%;
            &:first-child::after{
                left: -8px;
                top: 58%;
            }
        }
    }
}
